MIC MOD choosing capacitors

  • Thread starter Thread starter Disease8
  • Start date Start date
Disease8

Disease8

New member
:confused:

Hi just trying to buy some capacitors for the mxl 603/Apex180 mod. In this case I went for the Apex 180's.
I was looking at the mod here.
I already had to work out that "Styroflex" means "Polystyrene".
Now i am stuck again with the specs.
I know its 1000pf polystyrene that I need but what tolerance? and voltage?
I think low voltage like 50v will be ok? But as for tolerance I haven't got a clue.
If someone could shed some light I would be most happy :-)
 
Ok so i bought some!

2x NOS SUFLEX 1000pf POLYSTYRENE CAPACITORS 1n0 0.001uF on eBay (end time 15-Mar-11 22:03:07 GMT)


20x Radial Polystyrene Capacitors 33pF 50v 5% STV-33P on eBay (end time 05-Mar-11 20:26:50 GMT)

Metallised Polypropylene Capacitors : Polypropylene : Maplin

Screwed up and got some 0.33 polystyrene ones so got more around that capacitence as metal film (the maplin ones).

If you look in Gus's mod he advices 0.22uf but later on people are saying higher gets a better sound so i went for 0.47uf.

My only concern is the voltages are wrong how much does this matter? They are higher than 50v which I think is the recommended amount.
 
A higher voltage rating that specified probably isn't problem for sound, but the higher the voltage rating (usually) the physically bigger the capacitor, and so you can run into problems actually fitting the things into the case. But you're prolly in good shape.

As for the tolerances, if you're modding two mics, lower tolerances are better, but if you get a handful of capacitors (that is, more than you need), you can just match them yourself using a multimeter, use the best matched ones, and then the tolerance doesn't matter (assuming you found good matches).

If you're just modding one mic, then the tolerance on the 1000pf one isn't as important, but it's still nice to match the others.

disclaimer: I don't know what I'm saying
 
I have a hunch those aren't ceramic disc in his pictures to begin with, but that aside, 1000pF is pretty small, so voltage ratings can go higher and still be physically small. If your phantom power is +48VDC, then any capacitor higher than would work. Some people double that up, so a 100VDC capacitor should still be very small. A 50VDC capacitor would be fine, but if there is a power surge (unlikely), there might be problems. I doubt this would happen, as you can see 16VDC filters, so it's probably not directly connected to the phantom power supply.
 
this guy is a legend:
Dear dmonicdom,

Hi Dom,
I have intercepted the mailbag, and have matched the caps for you @ 991pf and 992pf almost 0.1% match!
Kind regards
Rob

- valvesetc

regarding: 2x NOS SUFLEX 1000pf POLYSTYRENE CAPACITORS 1n0 0.001uF on eBay (end time 15-Mar-11 22:03:07 GMT)
 
470nF is .47uF, and the 500VAC rating is the head scratcher. Those you see as line bypass capacitors, but 470nF is way too high for UL, CSA, or whatever you have in England. Weird value for a crossover circuit. I have no idea what the Hell you have there.
 
ranjam said:
470nF is .47uF, and the 500VAC rating is the head scratcher. Those you see as line bypass capacitors, but 470nF is way too high for UL, CSA, or whatever you have in England. Weird value for a crossover circuit. I have no idea what the Hell you have there.
Click to expand...

Hmmm I have a strange bunch of caps now lol...

The ones that i hoped would work are too big:

2x NOS SUFLEX 1000pf POLYSTYRENE CAPACITORS 1n0 0.001uF

But they might fit down the other end of the mic away from the capsule end. But I would have to connect them with wires back to where they were soldered into the pcb.
Would this work?

If not I have a pack of Radial Polyetyrene Caps 33pf 50v 5% that will def work...

I am getting to the point where I am nearly ready to start modding..
Bit nervous about that..
 
You must log in or register to reply here.
Back
Top